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The ISS is easily mistaken for a fast-moving aircraft, but can be identified by the fact it has no flashing lights. When supply vehicles dock with the station, it can even be possible to see them as a separate point of light.

Its exact position changes from night to night and because it does not follow the same path each time it orbits, each viewing opportunity varies in quality.

Typically sightings are possible for several weeks at a time before the ISS vanishes from sight for a similar period.

Details of where and when to spot the ISS vary significantly across the country, but the Nasa website has a list of viewing opportunities from dozens of towns and cities in the UK.

This week it will become visible again after a period of absence, with early morning viewings possible in the south from Tuesday. From the first week of June it can also be seen in the evening as well as morning hours.

Dr Tim O'Brien of the Jodrell Bank Observatory said: "Its visibility depends on its position in relation to this position on Earth. You get periods of visibility and then periods when it is not visible, or isn't as bright as at other times.

"Sometimes sightings are lower down, sometimes they are higher up, sometimes they are incredibly bright and sometimes fainter. It will get brighter towards the end of the month."

The next sighting from London will be at 3.46am on Tuesday, lasting about three minutes. It will arrive to the south at ten degrees above the horizon – about the height of a fist on an outstretched arm – and reach a maximum of 14 degrees elevation before passing out of sight to the east-south-east.

Better opportunities may come early on Thursday and Saturday mornings when the crossings will last at least five minutes and the station will be positioned higher in the sky, meaning it will be visible further north.